Cisco AnyConnect Secure Mobility Client Arbitrary Code Execution Vulnerability [CVE-2020-3556]

CVE number – CVE-2020-3556

A vulnerability in the interprocess communication (IPC) channel of Cisco AnyConnect Secure Mobility Client Software could allow an authenticated, local attacker to cause a targeted AnyConnect user to execute a malicious script.

The vulnerability is due to a lack of authentication to the IPC listener. An attacker could exploit this vulnerability by sending crafted IPC messages to the AnyConnect client IPC listener. A successful exploit could allow an attacker to cause the targeted AnyConnect user to execute a script. This script would execute with the privileges of the targeted AnyConnect user.

Note: To successfully exploit this vulnerability, an attacker would need all of the following:

• Valid user credentials on the system on which the AnyConnect client is being run by the targeted user.
• To be able to log in to that system while the targeted user either has an active AnyConnect session established or establishes a new AnyConnect session.
• To be able to execute code on that system.

Cisco has not released software updates that address this vulnerability. There are workarounds that address this vulnerability.

Vulnerable Products

This vulnerability affects all versions of the Cisco AnyConnect Secure Mobility Client Software for the following platforms if they have a vulnerable configuration.

• AnyConnect Secure Mobility Client for Windows
• AnyConnect Secure Mobility Client for MacOS
• AnyConnect Secure Mobility Client for Linux

For further information and any workarounds visit – https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-anyconnect-ipc-KfQO9QhK